1. Field of the Invention
The present invention relates to a cooking appliance such as a microwave oven, and more particularly to a support structure at a rear side of an internal compartment, i.e., a heating chamber of a cooking appliance.
2. Prior Art Discussion
In general, in a microwave oven, as shown in FIG. 3, an internal compartment 1 is composed to a front plate 2, a main base plate 3 in a U like form, a ceiling plate 4 and a rear plate 5. The internal compartment 1 is held to an external housing by fixing the rear side of the internal compartment 1 to a back plate 6 of the external housing using screws.
Each member of the internal compartment 1 is apt to be made of thin metal sheet of thickness 0.4-0.5 mm because of the cost reduction in recent years. If such a thin sheet is provided with a hole and a screw is threadably fixed therethrough, problems in strength will occur, and there is a fear of slippage of the screw resulting in a failure to hold the internal compartment.
Consequently, in the related art, as shown in FIGS. 4(a) and 4(b), the fixing is performed by screws 9 using a reinforcing plate 7 or a tap plate 8.
However, in the conventional structure as above described, since a separate part such as reinforcing plate or a tap plate is required, the number of parts or the cost of parts is increased and also the work efficiency decreases.